Jack of Harts

It was the orbital elevators that made us a true space faring species. We could only boost small numbers of people and cargo into orbit before then, leaving most exploration to major government or semi-government agencies like NASA. But once we built the elevators we could send people and cargo up or down all day, every day. And once you get out of the gravity well it takes very little fuel to go anywhere in the solar system. Interstellar travel was still too expensive for the masses, but the solar system was our playground and humanity spread throughout it in a matter of decades.